Least privilege
security tab
Yes, they have no effective permissions.
Security Group
security groups
Assigning users to groups simplifies the administration of security by allowing permissions to be assigned to users based on their groups rather than having to assign permissions to each user.
genetic recombination
what dicates the reason a security officer can escalate the use of force
No one does unless you allowed remote access. Check it in your comp. settings (security or permissions/users)
check the local security policy check all user accounts
The three classes of security a file will have in a Unix-like system are "User", "Group" and "Other". Within each class are three permissions: Read, Write, and Execute. This Wikipedia article on CHMOD (the command to change permissions for a file) is a pretty good source for further details.
Security is one of the key concern of a database administrator. Security can be added to the user, object etc. An object (table,views,stored procedures etc) can have multiple permissions. A database administrator can grant revoke permissions to the objects. Security is implemented based on the data sensitiveness also. If there is a table for password, make sure that only it's encrypted and can be accessible through administrator only.
Collective Security / Defense